A one-year course of 18 doses of pembrolizumab significantly reduced the risk of recurrence for patients with stage 3 melanoma who were at high risk of recurrence after surgery, according to data from the KEYNOTE-054/EORTC 1325-MG phase III clinical trial, presented at the AACR Annual Meeting 2018, April 14–18.

“A patient’s risk of recurrence depends on the number of lymph nodes affected and the tumour load. Those classified as having a high risk of recurrence have one or more regional lymph nodes with melanoma metastasis. In the case of a single positive node, the diameter must be greater than 1 millimetre.

“We were pleased to see that adjuvant pembrolizumab, given as a flat dose of 200 milligrams every three weeks after surgery for up to a year, which is 18 doses, significantly reduced the risk of recurrence for patients with high-risk stage 3 melanoma that has been completely resected,” continued Eggermont.

“We hope that these data will lead to regulators in the United States and Europe approving pembrolizumab as a new treatment option for these patients.”

For all the patients randomised to pembrolizumab, the 12-month recurrence-free survival rate was 75.4 percent, compared with 61.0 percent for all those randomised to placebo.

Thus, overall, patients randomised to pembrolizumab were 43 percent less likely to have recurrence.

The FDA approved ipilumumab and nivolumab for use as an adjuvant treatment for patients with high-risk stage 3 melanoma that has been completely resected in October 2015 and December 2017, respectively.

Eggermont and colleagues enrolled 1,019 patients with stage 3 melanoma who were at high risk of recurrence after complete resection of their tumours in the KEYNOTE-054/EORTC 1325-MG phase III clinical trial.

Patients were randomised 1:1 to a flat dose of 200 milligrams of pembrolizumab or placebo every three weeks for a total of 18 doses or until disease recurrence or unacceptable toxicity.